1. Field of the Invention
The present invention relates to a reflector, a liquid crystal display (LCD) device having the reflector, a method of manufacturing a reflector, and a method of manufacturing an LCD device having the reflector. More specifically, the present invention relates to a structure of a reflector to be formed on a substrate of an LCD device, a reflective or semi-transmissive LCD device having the reflector, and methods of manufacturing the reflector and the LCD device having the reflector.
2. Description of the Related Art
LCD devices have favorable features of small sizes, thin profiles, and lower power consumption and are therefore put into practical use in a broad range of applications including office automation equipment, and portable devices. Unlike a cathode ray tube (CRT) or an electroluminescence (EL) display device, LCD devices do not include a light-emitting function by themselves. Accordingly, a transmissive LCD device is provided with a backlight source so that displays are controlled by transmission amount of backlight through an LCD panel. By use of the backlight, this transmissive LCD device can achieve a bright screen without depending on ambient environments. On the other hand, this type of the LCD device has a problem of short operating time in mobile use particularly when it is driven by a battery power source. This is because the backlight source consumes high power during display operation.
A reflective LCD device configured to display images by use of ambient light has been proposed in order to solve the problem of high power consumption by the backlight source. This reflective LCD device is provided with a reflector instead of the backlight source, so that displays are controlled by transmission amount of the ambient light reflected by the reflector through the LCD panel. Thus, by employing such a reflective LCD device, it is possible to aim to achieve reduction in power consumption as well as reduction in size and weight. In the meantime, this LCD device has a problem of deterioration in visibility in a dark ambient environment.
Accordingly, there is disclosed an LCD device in which each pixel includes a transmissive region and a reflective region in order to prevent an increase in power consumption attributable to the backlight source and deterioration in visibility attributable to the ambient environment. An LCD device having both functions of the transmissive LCD device and the reflective LCD device will be hereinafter referred to as a semi-transmissive reflective LCD device. Usually, this semi-transmissive reflective LCD device is configured to form a reflector at a part (a reflective region) of an active-matrix substrate including switching elements such as thin film transistors (TFTs) and to generate diffuse reflection of ambient light by use of this reflector.
The reflective LCD device or the semi-transmissive reflective LCD device is provided with a resin layer having a concavo-convex shape and then the reflector is formed by providing a reflective film on the resin layer. This LCD device pursues a bright display under a condition of strong external light by applying this structure. The concavo-convex shape of the resin layer is formed by exposing and developing portions to be concavities and convexities by a photolithography method and then subjecting these portions to a heat treatment. However, by using the manufacturing methods and the structures of the related art, it is difficult to fabricate a reflector having a sufficiently bright reflection characteristic at low costs.